Hollow sheet metal structure



Feb. 28, 1967 s. J. HUMANIC,

HOLLOW SHEET METAL STRUCTURE Filed Oct. 4, 1965 To Sewer 4 From Ware/Supply U0 Sewer 7'0 E level/n g Mechanism m 2 From Water Supply 2 Sheets-Sheet 1 From Wafer Supp/y 7-0 L Sewer 48 36 24 *54 36 From Water Supply To Sewer 7'0 Sewer INVENTOR.

STEVEN J. HUMAN/C Mew Attorney Feb. 28, 1967 Filed Oct. 4, 1965 I s. J. HUMANIC HOLLOW SHEET METAL STRUCTURE 2 Sheets-Sheet z l/VVENTOR. STEVEN J. HUMAN/C A t rarney United States Patent Oflfice 3,306,268 Patented Feb. 28, 1967 3,306,268 HOLLOW SHEET METAL STRUCTURE Steven J. Humanic, Library, Pa., assignor to United States Steel Corporation, a corporation of Delaware Filed Oct. 4, 1965, Ser. No. 492,643 9 Claims. (Cl. 122-498) U.S. Patent N 0. Issue Date Inventor August 23, 1910. April 11, 1905. April 21, 1903. July 15, 1913. January 18, 1916. April 3, 1951. October 11, 1955. January 5, 1960. October 18, 1960.

Conventional hollow sheet metal structures, such as open hearth furnace doors, are provided with an open faced recess or pocket in the high temperature face, Which recess has a depth of about one-half of the thickness of the furnace door. This recess is provided with a refractory lining, either a plastic basic refractory lining, such as chrome ore (rammed on steel studs set in bottom wall of the recess) or a fire clay brick lining. Such refractory lining is subject to the intense heat in the melting chamber of the open hearth furnace and after about twelve heats, the portion of the refractory lining in the maximum heat zone, usually the top central portion of the furnace door, begins to burn off, thus materially reducing the weight of the stud type, water cooled or rammed furnace door. As a result of this weight loss malfunctioning of the counterweighted hoist system which raises and lowers such furnace door occurs. Further the bottom wall of the recess is exposed to the intense heat thus causing buckling or rupturing of such bottom wall, particularly adjacent the tie studs, utilized to hold the bottom Wall and the low temperature face plate together. Such buckling and rupturing is caused by'the expansion and contraction of the bottom wall when exposed to temperatures ranging from ambient temperature (about 4080 F.) to about 3200 F. and occurs in conventional open hearth doors after about eighty heats .in the first campaign for the furnace door and progressively after fewer heats in successive campaigns. Labor and material costs to repair the rammed-type furnace door are high.

It is the general object of the present invention to avoid and overcome the foregoing and other difiiculties of and objections to prior art practices by the provision of an improved open hearth furnace door which:

(1) has an operational life more than about five times greater than the operational life of a conventional water cooled refractory lined furnace door;

(2) has a constant weight or mass during its operational life, thus permitting satisfactory operation of the door-elevating mechanism and attendantly minimizing heat losses from the furnace heretofore caused by improper position of the furnace door with respect to the door frame;

(3) eliminates the need for the refractory lining and, in the case of the stud-type furnace door, the need for the lining studs;

(4) has repair costs about one-fifth the repair costs of the conventional refractory lined door;

(5) provides a two-way stretch adjacent the maximum heat zone of the furnace door thereby substantially eliminating buckling and splitting or rupturing of the high temperature inner face plate;

(6) provides controlled heating in the maximum heat zone of the furnace door by rapid conduction, convection and radiation of heat away from such maximum heat zone;

(7) provides a simple, rugged structure adjacent the maximum heat zone of the furnace door, which structure is resistant to buckling and splitting or rupturing of the high temperature face plate particularly adjacent tie stud welds; and

(8) provides complete, uniform and rapid cooling by fluid blanketing of the maximum heat zone of the furnace door, thereby substantially eliminating the deleterious high temperatures adjacent such maximum heat zone, which high temperatures are conducive to buckling and split-ting and rupturing of the high temperature face plate.

The aforesaid objects of the present invention, and other objects which will become apparent as the description proceeds, are achieved by providing an improved hollow furnace door for a high temperature furnace having a wall provided with a door aperture and having a door frame in the door aperture. The hollow furnace door is movable on the door frame from an open position to a closed position. The furnace door has a high temperature inner face plate disposed adjacent the door frame and a maximum heat zone. A low temperature outer face plate is opposite the high temperature inner face plate. Closure means are adjacent the high temperature inner face plate and the low temperature outer face plate and define with the high temperature inner face plate and the low temperature outer face plate a fluid chamber. A partition member is disposed in the maximum heat zone between the high temperature inner face plate and the low temperature outer face plate and divides the fluid chamber into a first fluid compartment and a second fluid compartment. This partition member provides two-way stretch in the furnace door adjacent the maximum heat zone and removes heat from the maximum heat zone to the closure means.

Each of the first fluid compartment and the second fluid compartment has a first conduit means connected thereto and is adapted to introduce a fluid into one corner thereof. A second conduit means is connected thereto and is adapted to remove fluid from an opposite corner thereof, thereby swirling the fluid through the maximum heat zone in a generally circular path between the closure means and the partition member and simultaneously removing a portion of the fluid therefrom and substantially reswirling the remainder of the fluid through the maximum heat zone in such generally circular path.

For a better understanding of the present invention reference should be had to the accompanying drawings, wherein like numerals of reference indicate similar parts throughout the several views and wherein:

FIGURE 1 is a fragmentary perspective view of a portion of a high temperature furnace wall showing the door frame and the improved furnace door of this invention;

FIGURE 2 is -a front elevational view of the furnace door showing the maximum heat zone and the swirling action of the fluid with the inner plate partially broken away;

FIGURE 3 is a in FIGURE 2;

FIGURE 4 is a side elevational view of the furnace door taken from the right side of FIGURE 2;

FIGURE 5 is a fragmentary view similar to FIGURE 2 of an alternative embodiment and showing the inner plate; and

plan view of the furnace door shown FIGURES 6 and 7 are views similar to FIGURE of further alternative embodiments.

Although the principles of the present invention are broadly applicable to hollow sheet metal structures, the hollow sheet metal structure of the present invention is particularly adapted for use as a hollow door on an open hearth furnace and hence it has been so illustrated and will be so described.

With specific reference to the form of the present invention illustrated in the drawings, and referring particularly to FIGURE 1, a front wall of an open hearth furnace is indicated generally by the reference numeral 10.

This wall 10 has a door aperture 12 (FIGURE 1) and a water-cooled door frame 14 (of the type shown in the above mentioned US. Patent No. 1,168,647) disposed in the door aperture 12. A hollow furnace door 16 (FIGURES 1, 2) of this invention is movable on the door frame 14 from an open position (not shown) to a closed position (FIGURE 1) by an elevating mechanism.

This elevating mechanism has a hoisting chain 18 (FIG- URE 1) disposed behind a superstructure 19 and extending from a counterweighted elevating means, such as a hoist (not shown) to a door hanger 20 (FIGURE 1), which door hanger 20 is connected by a linkage 22 (FIG- URE 1) to clevises 24 (FIGURES 1-4) upstanding from the furnace door 16. For safety purposes, a safety chain 26 (FIGURE 1) connects an eye 27 (FIGURES 1-4) to a bolt 28 on the superstructure 19 of the wall 10.

This furnace door 16 has a high temperature inner face plate 30 (FIGURES 3, 4), which face plate 30 is disposable adjacent the door frame 14 and is provided (when subjected to the heat of the melting chamber of the furnace) with a maximum heat zone Z (FIGURES 1 and 2). This maximum heat zone Z is determined by temperature measurements or approximated by the deterioration pattern of a conventional rammed-type furnace door (not shown). The shape of the door frame 14 and the height of the insulating means, suitably dolomite 31 (FIGURE 1) determine the generally elliptical shape of the maximum heat zone Z shown in FIG- URES 7 and 2.

A low temperature outer face plate 32 (FIGURES 1-4) is disposed opposite the inner face plate 30. C10- sure means, such as the side plates 34 (FIGURES l-4) and end plates 36 (FIGURES 2-4) are sealingly secured to the inner face plate 30 and outer face plate 32 and define with such inner face plate 30 and outer face plate 32 a fluid chamber 37 (FIGURES 2, 3). The closure means can be one integral member, as shown in FIGURE 4, and bottom end plate 36 is rounded at 36:: to prevent contact between such bottom end plate 36 and the door frame 14, thus extending the life of such bottom end plate 36. In this fluid chamber 37, a partition member 38 (FIGURE 2) is disposed in the maximum heat zone Z between the inner face plate 30 and outer face plate 32 and in engagement with a wicket 39 (FIGURES 1, 2, 4) for sealingly dividing the fluid chamber 37 into a first fiuid compartment 40 and a second fluid compartment 42 (FIGURES 2-4). This partition member 38 provides two-way stretch to the furnace door 16 adjacent the maximum heat zone Z and removes heat from the maximum heat zone Z to the closure means and face plates 30, 32 by means of radiation, convection and conduction.

It should be noted from a consideration of FIGURE 2 that the maximum heat zone Z contains a minimum number of tie studs 44 (between the face plates 30, 32). In FIGURES 2, 6 only two such tie studs 44 are shown, one tie stud 44 on each side of of the partition member 38, thereby facilitating the two-way stretch properties of the furnace door 16.

Each of the compartments 40, 42 have a first conduit means, suitably an inlet line 46 (FIGURE 1) from a water supply, such as the plant service water system, an inlet 48 (FIGURES 1-4) in furnace door 16 and a guide member 50 (FIGURES 2, 3) within the furnace door 16 for introducing a fluid, such as river water, into one corner 52 (FIGURE 2) of the compartments 4%, 42. A second conduit means, suitably an outlet 54 in the furnace door 16 and an outlet line 56 (extending to a sewer,- such as a flume discharge and sewer) removes the c'i'rculated river water from an opposite corner 58 (FIGURE 2) of the compartments 40, 42. The river water in the compartments 40, 42 swirls through the rriaximurri heat zone Z in a generally circular path between the closure means and the partition members 38 (along the line of the arrows marked with a subscript 1) splitting off through outlet 54 and in the generally circular path in-' dicated by the arrows marked with a subscript 2.- The outlet 54 removes a portion of the river water during the first pass and reswirls substantially the remainder of the river water through the maximum heat zone Z in the generally circular path indicated by the arrows with subscript 2 until such remainder rejoins the initial pass flow' and is removed from the compartments 40, 42 by the outlet 54. In each compartment 40, 42 random vortex zones V (FIGURE 2) are created by the violent movement of the river water therein and such vortex zones V enhance the cooling efiect of the river water on the maximum heat zone Z.

Alternative embodiments It will be understood by those skilled in the art that alternatively, as shown in FIGURE 5, the fluid flow may be reversed, entering through inlet 48 at corner 52 and exiting at corner 58 through guide member 50 and an outlet 54 I I In FIGURE 6 an outlet 54 is disposed within a bafiie chamber 60 defined by a bafi le 62, the top end plate 36 and the face plates 30, 32. For the purpose of stfearri= lining the flow path of the river water, guide member 50 is shortened and guides 64a, 64b, are employed. These guides 64a, 64b reinforce the furnace door 16 and im-' prove the heat resistance characteristics of such furnace door 16 As shown in FIGURE 7 river water enters compart= ment 42 via inlet 48' and guide member 50 and exits therefrom through outlet 54 V v I It will be recognized by those skilled in the art that the objects of the present invention have been achieved by providing improved open hearth furnace doors 16 (FIG-' URES 1-4), 16 (FIGURE 5), 16 (FIGURE 6) and 16' (FIGURE 7) which doors have an operational life more than about five times greater than the operational life of a conventional water cooled refractory lined fur= nace door (not shown). Such improved furnace doors 16, etc. have a constant weight or mass during their op= erational life, thus permitting satisfactory operation of the door-elevating mechanism and attendantly reducing heat losses from the furnace caused by improper position of the furnace doors 16, etc. with respect to the door frame 14. The doors 16 etc. eliminate the need for the refractory lining and in the case of the stud-type furnace door the need for the lining studs and have repair costs about one fifth the repair costs of the conventional refractory lined door. The partition member 38 (FIG- URES 1-4) provides a two-way stretch adjacent the maximum heat zone Z of the furnace doors 16 etc., thereby substantially eliminating buckling and splitting or rupturing of the high temperature face plate 30. Such partition member 38 also provides controlled heating in the maximum heat zone Z of the furnace doors 16, etc. by rapid conduction, convection and radiation of heat away from such maximum heat zone Z. The simple, rugged structure of the partition member 38 adjacent the maximum heat zone Z of the furnace doors 16, etc. is resistant to buckling and splitting or rupturing of the high temperature face plate 30, particularly adjacent tie stud welds 44. The inlet means (inlet line 46, inlet 48 and guide member 59, FIGURE 1, etc.) and outlet means (outlet 54, FIGURE 1, etc.) provide complete, uniform and rapid fluid blanketing and hence maximum cooling of the maximum heat zone Z of the furnace doors 16,

etc., thereby substantially eliminating the deleterious high temperatures adjacent such maximum heat zone Z, which high temperatures are conducive to buckling and splitting and rupturing of the high temperature face plate 30.

While in accordance with the patent statutes preferred and alternative embodiments of the present invention has been illustrated and described in detail, it is to be particularly understood that the invention is not limited thereto or thereby.

I claim:

1. For a high temperature furnace having a wall provided with a door aperture and having a door frame in said door aperture, a hollow furnace door movable on said door frame from an open position to a closed position, said furnace door having:

(a) a high temperature inner face plate disposed adjacent said door frame and having a maximum heat zone,

(b) a low temperature outer face plate opposite said high temperature inner face plate,

(c) closure means adjacent said high temperature inner face plate and said low temperature outer face plate and defining with said high temperature inner face plate and said low temperature outer face plate a fluid chamber,

((1) a partition member disposed in said maximum heat zone between said high temperature inner face plate and said low temperature outer face plate and dividing said fluid chamber into a first fluid compaitment and a second fluid compartment, said partition member providing two-way stretch to said furnace door adjacent said maximum heat zone and removing heat from said maximum heat zone to said closure means,

(e) each of said first fluid compartment and said second fluid compartment having:

( 1) a first conduit means connected thereto and adapted to introduce a fluid into one corner thereof,

(2) a second conduit means connected thereto and adapted to remove fluid from an opposite corner thereof, thereby swirling said fluid through said maximum heat zone in a generally circular path between said closure means and said partition member and simultaneously removing a portion of said fluid therefrom and reswirling the remainder of said fluid through said maximum heat zone in said generally circular path,

(3) a partition member connected to one of the said first conduit means and said second conduit means for separating the portion of said fluid carried by said partition member from the remainder of said fluid in said fluid compartment to maximize swirling and reswirling of said fluid.

2. The furnace door recited in claim 1 wherein said first conduit means is disposed adjacent said partition member.

3. The furnace door recited in claim 1 wherein said first conduit means is disposed adjacent said closure means.

4. The furnace door recited in claim 1 wherein said second conduit means is disposed adjacent said partition member.

5. The furnace door recited in claim 1 wherein said second conduit means is disposed adjacent said closure means.

6. The furnace door recited in claim 1 wherein said closure means has a rounded bottom portion disposed adjacent said high temperature face plate.

7. The furnace door recited in claim 1 wherein said first conduit means is provided with a first guide means.

8. The furnace door recited in claim 1 wherein said second conduit means is provided with a second guide means.

9. The furnace door recited in claim 1 and having guide means adjacent said partition member, said first conduit means and said second conduit means for streamlining fluid flow through said fluid compartments.

References Cited by the Examiner UNITED STATES PATENTS 1,191,518 7/1916 Knox 122-498 1,391,196 9/1921 Law 122-498 3,106,911 10/1963 Traina 122-499 3,198,178 8/1965 Reighart 122498 KENNETH W. SPRAGUE, Primary Examiner. 

1. FOR A HIGH TEMPERATURE FURNACE HAVING A WALL PROVIDED WITH A DOOR APERTURE AND HAVING A DOOR FRAME IN SAID DOOR APERTURE, A HOLLOW FURNACE DOOR MOVABLE ON SAID DOOR FRAME FROM AN OPEN POSITION TO A CLOSED POSITION, SAID FURNACE DOOR HAVING: (A) A HIGH TEMPERATURE INNER FACE PLATE DISPOSED ADJACENT SAID DOOR FRAME AND HAVING A MAXIMUM HEAT ZONE, (B) A LOW TEMPERATURE OUTER FACE PLATE OPPOSITE SAID HIGH TEMPERATURE INNER FACE PLATE, (C) CLOSURE MEANS ADJACENT SAID HIGH TEMPERATURE INNER FACE PLATE AND SAID LOW TEMPERATURE OUTER FACE PLATE AND DEFINING WITH SAID HIGH TEMPERATURE INNER FACE PLATE AND SAID LOW TEMPERATURE OUTER FACE PLATE A FLUID CHAMBER, (D) A PARTITION MEMBER DISPOSED IN SAID MAXIMUM HEAT ZONE BETWEEN SAID HIGH TEMPERATURE INNER FACE PLATE AND SAID LOW TEMPERATURE OUTER FACE PLATE AND DIVIDING SAID FLUID CHAMBER INTO A FIRST FLUID COMPARTMENT AND A SECOND FLUID COMPARTMENT, SAID PARTITION MEMBER PROVIDING TWO-WAY STRETCH TO SAID FURNACE DOOR ADJACENT SAID MAXIMUM HEAT ZONE AND REMOVING HEAT FROM SAID MAXIMUM HEAT ZONE TO SAID CLOSURE MEANS, (E) EACH OF SAID FIRST FLUID COMPARTMENT AND SAID SECOND FLUID COMPARTMENT HAVING: (1) A FIRST CONDUIT MEANS CONNECTED THERETO AND ADAPTED TO INTRODUCE A FLUID INTO ONE CORNER THEREOF, (2) A SECOND CONDUIT MEANS CONNECTED THERETO AND ADAPTED TO REMOVE FLUID FROM AN OPPOSITE CORNER THEREOF, THEREBY SWIRLING SAID FLUID THROUGH SAID MAXIMUM HEAT ZONE IN A GENERALLY CIRCULAR PATH BETWEEN SAID CLOSURE MEANS AND SAID PARTITION MEMBER AND SIMULTANEOUSLY REMOVING A PORTION OF SAID FLUID THEREFROM AND RESWIRLING THE REMAINDER OF SAID FLUID THROUGH SAID MAXIMUM HEAT ZONE IN SAID GENERALLY CIRCULAR PATH, (3) A PARTITION MEMBER CONNECTED TO ONE OF THE SAID FIRST CONDUIT MEANS AND SAID SECOND CONDUIT MEANS FOR SEPARATING THE PORTION OF SAID FLUID CARRIED BY SAID PARTITION MEMBER FROM THE REMAINDER OF SAID FLUID IN SAID FLUID COMPARTMENT TO MAXIMIZE SWIRLING AND RESWIRLING OF SAID FLUID. 